Bytearray

#python  

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Table of Content

The bytearray class is a mutable sequence of integers in the range 0 <= x < 256.

data = bytearray(10)
data
bytearray(b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00')

mutable vs immutable

A mutable object can be changed after it’s created, and an immutable object can’t.

bytearray, bytes and string

bytes and bytearray classes both hold arrays of bytes, where each byte can take on a value between 0 and 255. The primary difference is that a bytes object is immutable, meaning that once created, you cannot modify its elements. By contrast, a bytearray object allows you to modify its elements

# create array with 10 bytes
data = bytearray(10)
b = bytes(data)
>>> b
b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'

my_str = "abcd"
>>> my_data = bytearray(my_str, 'ascii')
>>> my_data
bytearray(b'abcd')
>>> len(my_data)
4

>>> my_data = bytearray(my_str, 'utf-16')
>>> len(my_data)
10

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more

>>> data=bytearray([65,66,67])
>>> data
bytearray(b'ABC')

# show etch value as hex
>>> [hex(c) for c in data]
['0x41', '0x42', '0x43']

# append
>>> data.append(68)
data
bytearray(b'ABCD')

# replace
>>> data[1:3] = [0x62, 0x63]
>>> data
bytearray(b'AbcD')

# extend
>>> data.extend([0x45, 0x46])
>>> data
bytearray(b'AbcDEF')

# extend
>>> new_data = bytearray(b"GH")
>>> new_data
bytearray(b'GH')
>>> data + new_data
bytearray(b'AbcDEFGH')